Timer



July 26, 1932. MOULD 1,868,754

. TIMER I Filed July 11, 1931 ill.

INVENTOR.

=M BY W w v M OM/M A TTORNEYS Patented 26, 1932 um'rso STATES PATENT. orrrce JAMES A. MOULD, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO GAB FOOL PATENTS COB- PORATION, OF'TJHICAGO, ILLINOIS, ACOBPORATION OF DELAWARE 'rmna Application filed Jul 11,1931. Serial 115,550,155.

This invention relates to improvements in timers. a

It is the object of the invention to provide'a novel and improved timer for an in ternal combustion hammer or like engine wherein it is desirable that the timer be actuated directly from the piston; that the timer ride directly on the face of the piston as distinguished from any longitudinal oove therein; and that the timer contacts normally open.

In the drawing:

Figure 1 is a vertical axial section through an internal combustion hammer equipped with a timer'embodying this invention.

.Figure 2 is a fragmentary section showing a modified piston construction.

Figure 3 is an enlarged plan view of the head of the piston used in the device shown in Figure 2.

Like arts are identified by the same reference c aracters through the several views.

In the particular device disclosed the cylinder 4 in which piston 5 reciprocates is provided with a jacket 6 having cooling fins 7 a for radiating head conducted thereto by a liquid in the jacket. The cylinder isprovided with a detachable head 8 having a jacket extension 9.

An anvil 10 is mounted for limited reciprocation in the lower end of the cylinder, its

movement being limited by the retainer 11 for tool 12. Compression sprin s 14 and 15 of different strength and characteristics encircle a hammer 19 carried by the piston and are of such strength as to be adapted toreturn the piston during its compression stroke. The purpose of heavier spring 14 is toprovide a resilient seat for the active 5 ring 15 whereby to absorb impact shocks of ammer 19 on anvil 10 which would otherwise crystallize the return spring.

Mounted on the cylinder below the combustion chamber portion thereof is a fuel tank 20 including unitarily a carbureting device or mixing valve at 21 from which manifold passage-22 leads through port 23 into the sub-piston compression space in cglinder 4, thence transfer passage 24 leads t rough the cylinder casting to an intermediate point in the cylinder wall uncovered by the movement of piston 5 inthe course of its reciprocation for the delivery of a charge to the combustion chamber in the cylinder is a grounded contact 27 adjustable in the path of oscillation of a moving contact 28 carried by a lever 29 pressed by spring 30 toward contact closing position. The lever is normally held in contact opening position by a plunger 31 which acts as a cam follower to ride upon a cam integral with the iston. The cam follower plunger 31 is preferably provided with an antifriction roller 32.

To avoid longitudinal channeling of the Within timer case 26 an the wall of the A piston across the transfer passage 24 I prefer that the roller 32 should ride directly on, the face of the piston throughout most of the piston movement. A shallow notch or groove 33 is disposed in the side of the piston skirt ,near the lower end thereof to receive theroller momentarily just before the piston reaches the top of its stroke. This disposition of the partsnot only gives proper timing but ensures that the contacts will not be closedwhen the piston is at rest, nor at any other time except incidentto properly timed ignition.

In the Figure lconstruction the notch or groove 33 will be understood to have no appreci'able peripheral extent and inlorder to maintainit in angular registry with the cam follower I provide elsewhere in the piston a longitudinal groove at 35 with which a contering pin 36 is engaged.

The construction shown in Figure 2 is similar to that described with the exception that the groove 33 extends peripherally completely around the piston 5. This-arrangement makes the groove 35 and pin 36 unnecessary but requires the use of a peculiar baf-' fie 37 on the piston head with radial wings 38 so arranged that inany rotative pos tlon of the piston such wings will intercept the path of the charge entering the cylinder through transfer passage 24 to prevent such charge from passing directly through the exhaust port 39.

claim:

1. The combination with an engine cylinder and a iston having a relieved peripheral surface, 0 a timer deriving motion directly from the piston and comprising a fixed contact, a movable contact, and avcam follower .connected with the movable contact and ridprovided with a peripheral recess of such limited axial extent as to permit the cam follower only momentary engagement in the recess for the closing of said contacts in the movement of the piston. 3. The combination with a pair of relatively movable timing contacts and a contact actuator comprising acam follower, of. a cylinder upon which said cam follower is mounted for reciprocation, and a piston operable in the cylinder and provided with a generally cylindrical surface upon which said cam fol-- lower normally rides, said piston having a relieved peripheral portion registerable with the cam follower adjacent one extreme piston position and adapted to permit suflicient movement of the cam follower to close the timer contacts.

4. The combination with a pair of relative- 1y movable timing contacts andacontact ac tuator comprising a cam follower. of a cylinder upon which said cam follower is mounted ment, its relieved peripheral for reciprocation, and a pistonoperable in the cylinder and provided with a generally cylindrical surface upon which said cam follower normally rides, said piston having a. relieved peripheral portion registerable with the cam follower adjacent one extreme piston position and adapted to permit sufficient movement of the cam follower to close the timer contacts, together with means for confining said piston against angular displaceportion being of limited peripheral extent.

5. The combination with a pair of relatively movable timer contacts and a contact actuator normally maintaining said contacts separated and comprising a cam follower, of a piston provided with a peripheral. groove registerable with said cam follower and a generally. cylindrical surface upon which said cam follower rides except when engaged in said groove, said piston being reciprocable aecavea in the cylinder and freely rotatable with re--.

spect thereto.

6. The combination with a pair of relagenerally cylindrical surface upon which said cam follower rides except when engaged in said groove, said piston being reciprocable in the cylinder and freely rotatable with respect thereto, together with a baflie on the top of said plston effective to interrupt gasoline movement across the face of the piston irrespective of the angular position thereof.

7 In a two cycle engine, the combination with a cylinder having transfer and exhaust ports, of a piston reciprocable across said ports and rotatable within the cylinder, said piston being provided with a peripheral groove in its skirt portion, and a baflle on its face between said orts effective in any angular-position of the piston, a cam follower reciprocable through the cylinder wall and adapted to ride on the face of the piston and into the groove of its skirt, and a. air of normally separatedrelatively mova 1c contacts supported on the cylinder, one of said contacts beingconnected with said cam follower for engagement with the other contact when said a cam follower rides into the piston groove. v

8. In a device of the character described, the combination with a cylinder a piston reciprocable therein and providedin its skirt with a groove of limited axial and peripheral extent, means restricting said piston against rotation in the cylinder, a cam followerriding on the face of the piston in registry with said groove, and timer contacts mounted on the piston, one of which is connected with said cam follower for engagement with the other contact when said cam follower rides into the piston groove.

JAMES A. MUULD. 

